In the existing cable TV and satellite broadcasting, a fee-charging broadcasting system is employed.
As for accounting in the fee-charging broadcasting system, there are, for example, “pay-per-channel” in which the viewer pays a fixed charge for a specific channel every month to watch the channel, and “pay-per-view” in which a charge is set for each program and the viewer pays the charges of programs he/she has watched.
These charges are collected as follows. In the accounting system like pay-per-channel, after the viewer has made a contract of viewing a specific channel, a fixed charge for the channel is automatically collected by direct debit from a specified account. On the other hand, in the accounting system like pay-per-view, the transmitting end gets the history of viewing such as the title and time of a program the viewer has watched, and collects a charge according to the history of viewing. In order to get the history of viewing, the following methods have been employed: a method of transmitting the history of viewing and an IRD_ID which is an ID for identifying an IRD (Integrated Receiver Decoder) used for the viewing, from the receiving end to the transmitting end through a bidirectional cable; and a method of recording the history of viewing in an IC card, and periodically transmitting the history of viewing and a Card_ID which is an ID for identifying the IC card, to the transmitting end through a telephone line.
Accordingly, as for the contract system, regardless of the accounting system, i.e., not only in pay-per-view but also in pay-per-channel, a contract is made for each IRD and the charge is accounted and paid for each IRD. However, BS broadcasting employs an accounting system which is a kind of pay-per-channel, and a contract system in which a contract is made not for each IRD but for each family. That is, when the viewer makes a contract of viewing two channels, BS1ch and BS2ch, a charge for one contract is accounted to each family, and the charge for one contract is collected even if the family possesses two or more IRDs.
In recent years, it is not seldom that one family possesses plural TV sets, and it may safely be said that each member of a family owns a TV set. Further, the number of digital broadcasting channels is increasing. Accordingly, the number of families having plural IRDs and making contracts of viewing fee-charged broadcasts also increases. Further, because of versatility of digital broadcasting, it is expected that one company owns a large number of IRDs and utilizes fee-charged broadcasts.
Meanwhile, it is expected that the transmitting end of digital broadcasting will employ the contract system in units of groups like families or companies, as well as the existing accounting system in units of IRDs.
In the accounting system like pay-per-channel, it is possible to collect a fixed charge from each group, like in the existing BS broadcasting. In the accounting system like pay-per-view, however, the history of viewing is transmitted together with the IRD_ID or the Card_ID so that the transmitting end can grasp it in units of IRDs, not in units groups such as families or companies, each having plural IRDs.
Further, considering the versatility of undertaking in digital broadcasting and the great number of channels, it is desired that the viewer can select either the IRD-unit contract or the group-unit contract according to the carrier, channel, program, term, etc. to realize highly-flexible setting of contract systems.
The present invention is made to solve the above-described problems and it is an object of the present invention to provide a data transmission and reception method which realizes highly-flexible accounting on fee-charged data, in accordance with reception of the data in units of receivers or in units of groups each having plural receivers, and a receiver used for this method.